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S Pascual

Publications and source records attributed to S Pascual.

At least 37 records · Page 2Linked to original sources
PubMed2001

Element concentration variability in the whaleworm Anisakis simplex s.l.

Concentrations of the elements C, N, Fe, Na, K, Ca and Mg were analysed by chromatography and atomic absorption spectrometry in the whaleworm Anisakis simplex sensu lato. Nearly all mean inorganic element concentrations measured were higher in adult worms than in larval forms. Similarly, adults contained significantly higher nitrogen (i.e. lower C/N ratio values) than either eggs or larvae. Evidence for the significance of the parasitic life cycle stage and the systematic position of their hosts on the element concentration variability is discussed.

Animals↗
PubMed2001

Comparison of diagnostic methods for Helicobacter pylori infection in patients with upper gastrointestinal bleeding.

BACKGROUND: Accuracy of the most frequently used tests for diagnosing Helicobacter pylori infection in patients with upper gastrointestinal bleeding of peptic origin is determined. METHODS: Seventy-eight patients with endoscopically-proven upper gastrointestinal bleeding of peptic origin were included. The presence of H. pylori was considered when observed from the histology or, if negative, when serology and breath test were both positive. Accuracy of the rapid urease test was estimated in accordance with results obtained with other diagnostic methods. RESULTS: Lesions causing gastrointestinal bleeding were 56 duodenal ulcers, 13 gastric ulcers, 7 pyloric channel ulcers, 13 acute lesions of the gastric mucosa and 16 erosive duodenitis. H. pylori infection was present in 68 patients (87.2%). Forty-four patients had received non-steroidal anti-inflammatory drugs. The sensitivity/specificity (%) of the diagnostic methods was 48.5/100 for the rapid urease test, 91/77.8 for the breath test, 89.5/80 for serology and 86.3/100 for histology. The prior consumption of proton-pump inhibitors and antibiotics induced false-negative results in the rapid urease test and breath test, with no effect on serology and histology. CONCLUSIONS: The prevalence of H. pylori infection in patients with upper gastrointestinal bleeding from peptic lesions is high. Sensitivity of the rapid urease test for diagnosing H. pylori is low in this setting. Cases with negative rapid urease test need the combination of two or more additional tests if diagnosis is to be achieved. Cases with positive rapid urease test do not need further investigation for diagnosis.

Biopsy↗
PubMed2001

Anisakid infection in the European shag Phalacrocorax aristotelis aristotelis.

A total of 100 specimens of the European shag Phalacrocorax aristotelis aristotelis were examined for anisakid infections in the south-east North Atlantic. The taxonomic status of the anisakid nematodes was studied by structural analysis using light and scanning electron microscopy. Two species, Contracaecum septentrionale and C. rudolphii A (Nematoda: Ascaridoidea), occurred in the European shag with high values of prevalence and mean intensities of infection. These constitute new host records for both parasites, widening their known geographical distribution. Although the histopathology associated with the infections indicated that the anisakids did not have the potential to cause bird death, the parasites are capable of contributing to and hastening avian mortality in the case of heavily-parasitized cormorants and when stressed by xenobiotics and/or through a synergetic effect by other bioagressors.

Animals↗
PubMed2000

Elemental analysis of cetacean skull lesions associated with nematode infections.

The elemental composition of both healthy and eroded cetacean skulls associated with nematode infections was evaluated. A total of 27 samples of eroded and non-eroded prepared museum cetacean skulls were characterised by elemental (CHN), X-ray fluorescence, and X-ray diffraction methods. The inorganic composition and crystal line structure (hydroxylapatite-like minerals) were similar for both types of skull samples, but the CHN values clearly differed. The results suggest that the carbon-rich fraction is lost in eroded areas, probably as a result of glycosaminoglycan-degrading Crassicauda enzymes.

Animals↗
PubMed2000

Aggregata sagittata n. sp. (Apicomplexa: Aggregatidae), a coccidian parasite from the European flying squid Todarodes sagittatus (Mollusca: Cephalopoda).

A new species of the coccidian genus Aggregata Frenzel, 1885 (Apicomplexa, Aggregatidae) is described from the digestive tract of Todarodes sagittatus (Lamarck), an ommastrephid squid that lives in temperate waters in the northeastern Atlantic Ocean. Using light microscopy. oöcysts were 225-333 microm in length and 220-323 microm in width. Each oöcyst contained 600-1,000 sporocysts. Sporocysts were 16-18 microm in length and 15-17 microm in width, with a smooth surface and thick wall. Each sporocyst contained 4-8 sporozoites each with a length of 11-13 microm. This paper presents the description of a new Agregata species in a nerito-oceanic flying squid. Moreover. it extends the distribution of Aggregata to oceanic cephalopod host species. A. sagittata represents the third named species in the genus Aggregata in European waters and the seventh worldwide.

Animals↗
PubMed2000

Surface hydrophobicity, viability and efficacy in biological control of Penicillium oxalicum spores produced in aerial and submerged culture.

The surface hydrophobicity, viability and biocontrol ability of Penicillium oxalicum spores, produced either in aerial or submerged culture, were characterized. A phase distribution test showed that spores produced in both methods of culture were highly hydrophobic, but those produced in aerial culture were more hydrophobic. Spores stored fresh at either 4 or 25 degrees C retained a high viability (80%) after 27 weeks of storage, although aerial spores survived better. Freeze-drying severely affected viability, especially of submerged spores. Biocontrol ability against Fusarium oxysporum f. sp. lycopersici was studied in the growth chamber. Aerially- produced spores were more effective than submerged ones. Aerially-produced P. oxalicum spores appeared to have more advantages than those produced by submerged culture, in relation to both viability and efficacy. These results demonstrate that physiological changes occur depending on production conditions which significantly influences quality of the biocontrol agent.

Air↗
PubMed1999

Progression of cardiomyopathy and neuropathy after liver transplantation in a patient with familial amyloidotic polyneuropathy caused by tyrosine-77 transthyretin variant.

Familial amyloidotic polyneuropathy is an inherited form of amyloidosis associated with a mutant form of a protein called transthyretin. The Methionine-30 variant is the most frequent mutation observed. This disorder is caused by deposition of this protein as amyloid in several organs, such as the heart, kidneys, and peripheral nervous system. The disease is always progressive and fatal, and patients die 7 to 10 years after the onset of symptoms. Liver transplantation is at present the only choice for these patients because it provides improvement of symptoms and/or stops progression of the disease in most patients. We report the case of a patient who showed clear progression of cardiomyopathy and neuropathy after liver transplantation.

Amyloid Neuropathies↗
PubMed1999

Development of quinolone-resistant strains of Escherichia coli in stools of patients with cirrhosis undergoing norfloxacin prophylaxis: clinical consequences.

BACKGROUND/AIM: Norfloxacin prophylaxis decreases the incidence of bacterial infections in high-risk cirrhotic patients, but may promote the development of quinolone-resistant gram-negative bacteria in stools, and eventually lead to infections due to these bacteria. The aim of the study was to evaluate the prevalence of quinolone-resistant strains of E. coli in stools on admission, and the characteristics of any nosocomial infections. METHODS: Eighty-three consecutively hospitalized cirrhotic patients were included in this prospective study. The presence of quinolone-resistant strains of E. coli in stools on admission, and the characteristics of any nosocomial infections were recorded. RESULTS: Fourteen out of 83 patients (16.8%) showed quinolone-resistant E. coli in stools (Group I), and 69 did not (Group II). Thirteen out of 14 from Group I (92.8%) and 17/69 (24.6) from Group II had received primary or secondary prophylaxis with norfloxacin (p<0.001). During hospitalization, 12/12 (100%) of patients from Group I and 25/66 (37.8%) of patients from Group II underwent norfloxacin prophylaxis. Three bacterial infections in patients from Group I, 3 from Group II patients receiving norfloxacin and 16 from Group II patients not receiving norfloxacin were recorded (p<0.05). No infections due to quinolone-resistant E. coli were observed in patients colonized with these bacteria. Treatment with norfloxacin induced the development of quinolone-resistant E. coli in 6/14 (42.8%) patients in a mean time of 18.5+/-9.8 days. CONCLUSIONS: The development of quinolone-resistant strains of E. coli is significantly associated with previous administration of norfloxacin prophylaxis. However, in our series this fact is not associated with an increased incidence of quinolone-resistant E. coli or other gram-negative infections.

Aged↗
PubMed1999

Efficacy and safety of cardiomyotomy in patients with achalasia after failure of pneumatic dilatation.

In patients with achalasia, it has been suggested that pneumatic dilatation could make cardiomyotomy more difficult to perform, diminishing its efficacy and safety. Our aim was to evaluate the efficacy and safety of elective cardiomyotomy after failure of pneumatic dilatation in achalasia. During 14 years, 32 of 276 consecutive patients with achalasia have been operated on because of failure of dilatation therapy. Twenty patients have been followed-up for at least one year after surgery. After failure of dilatation, Heller's cardiomyotomy and 180 degrees anterior fundoplication were performed. Clinical status was evaluated before and after surgery. Lower esophageal sphincter pressure and esophageal body basal pressure were measured by manometry, esophageal diameter by barium meal, and gastroesophageal reflux by endoscopy and 24-hr esophageal pH monitoring. No technical difficulties were found during operation. Postoperative morbidity was infrequent and mortality was absent. Cardiomyotomy improved clinical status in 19 of 20 patients. The results of surgery were considered excellent or good in 16 patients (80%; CI: 56-94%). The pressure of the lower esophageal sphincter was significantly reduced, falling in most patients to under 10 mm Hg. Gastroesophageal reflux appeared after surgery in eight patients, four of them with endoscopic esophagitis, but it was controlled in all patients with medical therapy. In conclusion, cardiomyotomy is a safe and effective therapy in achalasia after failed pneumatic dilatation.

Adult↗
PubMed1999

Larval nematodes (Spiruroidea: Cystidicolidae) in Octopus vulgaris (Mollusca: Cephalopoda: Octopodidae) from the northeastern Atlantic Ocean.

Larval nematode parasites (Spiruroidea: Cystidicolidae) are recorded for the first time in Octopus vulgaris Cuvier, 1797 in the northeastern Atlantic Ocean. Prevalence was 16% and mean intensity was 1.46 worms/host. Body length of larval nematodes ranges from 8.3 to 9.3 mm, with a distance from the anterior end to nerve ring from 187.5 to 200 microm, and to excretory pore 194.6-350 microm. Anatomical characteristics, such as deirid, nerve ring, cephalic alae, excretory pore, pseudolabia amphids, sclerotized protuberance, and anus, examined using light microscopy (LM) or scanning electron microscopy (SEM), are illustrated. The nematode was designed as a cystidicolid "Type A" larva. The hemocytic infiltration present in the host tissue around the nematode capsule and the mechanical compression in the infected organs denote the pathogenicity of this nematode. In the study area, O. vulgaris may play the role of an intermediate or paratenic host in the nematode life cycle.

Animals↗
PubMed1998

Macroparasites in cetaceans stranded on the northwestern Spanish Atlantic coast.

An extensive parasitological survey was carried out during autopsy of 80 cetaceans representing 8 species within 4 families (Delphinus delphis, Stenella coeruleoalba, Tursiops truncatus, Grampus griseus, Globicephala melas, Kogia breviceps, Phocoena phocoena and Megaptera novaeangliae) collected on the northwestern Spanish Atlantic coast from February 1991 to October 1996. Two species of tetraphyllidean cestodes (Phyllobothrium delphini and Monorygma grimaldii), 2 ascaridoid nematodes (Anisakis simplex and A. physeteris), a single spirurid nematode (Crassicauda magna), 4 rhabditidiform nematodes (Halocercus delphini, H. invaginatus, Halocercus spp. and Stenurus globicephalae), a single polymorphynae acanthocephalan (Bolbosoma sp.), and 2 amphipods (Isocyamus delphini and Cyamus boopis) were found. This paper presents 6 new geographic records of macroparasites from cetaceans in temperate Atlanto-Iberian waters. A total of 11 component parasite species were found, mainly parasitizing the blubber, mesentery and stomach of cetaceans. Cetaceans harboured a suite of 4 generalist and 8 specialist species.

Animals↗
PubMed1998

Long-term recording of gastric ulcers in cetaceans stranded on the Galician (NW Spain) coast.

Long-term (1990-1996) results of recording gastric ulcers in the common dolphin are presented for the NW Spanish Atlantic coast. The occurrence and abundance of cetacean carcasses (belonging to 10 species) with gastric ulcers are also given and discussed. Ulcerations were detected in 17.2% of the animals examined, with 15% for common dolphins and 0 to 29.4% in other cetacean species. A positive relation was noted between ulcer counts and length and maturity of Delphinus delphis. Clusters of the nematode Anisakis simplex could be seen embedded in the gastric ulcers of 3 common dolphins. It could be concluded that gastric ulcers are non-fatal lesions in cetaceans stranded in NW Spain.

Animals↗
PubMed1998

Cancer dissemination during laparoscopic surgery: tubes, gas, and cells.

Port-site metastasis has been an unexpected finding after laparoscopic surgery in gastrointestinal cancer patients. No clear explanation exists for this phenomenom. The aims of this study were to evaluate the dissemination pattern in an experimental model of hepatocarcinoma in the rat and summarize current knowledge about the risks and the results of experimental studies on cancer dissemination during laparoscopic surgery. NDA-induced hepatocarcinoma was obtained in Sprague-Dawley rats. Tumors were manipulated during laparoscopy (group 1, n = 11) or laparotomy (group 2, n = 12). A Medline review of all experimental studies about the risk of cancer dissemination during laparoscopic surgery was undertaken. Both models were associated with implants in parietal wounds [1/11 in group 1 (9%) vs. 1/12 in group 2 (8%), p = NS]. Analysis of the current literature confirms that laparoscopy is associated with abdominal cell mobilization, and cells can be recovered in trocars, filtered exhaust gas, and instruments. Postoperative immunosuppression, the biologic aggressiveness of the tumor, and the gas used for laparoscopy also influence tumoral growth. Port-site metastases are secondary to multiple factors, including the technical skill of the surgeon, the biologic properties of the tumors, and local environmental aspects. Undoubtedly, laparoscopy can help disseminate aggressive tumors and should be reserved for diagnostic and staging procedures or for treatment of low-grade malignant tumors. Therapeutic resection, especially of colon cancer, should be restricted to prospective and randomized trials until there are enough hard data to rule out the clinical importance of this potentially severe complication.

Animals↗
PubMed1998

[Significance of the determination of antineutrophil cytoplasmic antibodies (ANCA) in ulcerative colitis and Crohn's disease].

We have studied prospectively 126 consecutive patients recruited with a known diagnosis of ulcerative colitis (UC; n = 78) and Crohn's disease (CD; n = 48) for anti-neutrophil cytoplasmatic antibodies (ANCA) by indirect immunofluorescence (IFI). Forty-six percent of UC and 18% of CD patients were found positive. The sensitivity and specificity for UC diagnosis were 0.46 and 0.81, respectively. We evaluated the pattern of IFI exhibited (perinuclear: pANCA and cytoplasmatic: cANCA). cANCA was found in 77% of CD and in only 30% of UC patients (p = 0.01). Sera from all CD patients were positive at a 1:20 dilution (and not at higher dilution) and it occurred in only in 14 UC patients (30%). Positive sera were also tested to characterize the antigen specificity by enzyme-linked immunosorbent assay (ELISA) but the antigenic nature of ANCA could not be identified in most cases. No differences were found between ANCA positive and ANCA negative patients regarding colonic extension (UC) or colonic involvement (CD), activity and colectomy. We conclude that ANCA may be a helpful diagnostic test in UC patients but it not seems to be important as a marker of activity. ANCA positivity can reflect disease heterogeneity in UC patients, perhaps discriminating those with immunologic disturbances.

Adolescent↗
PubMed1997

Endorectal ultrasonography in the follow-up of rectal cancer. Is it a better way to detect early local recurrence?

After curative surgery for rectal cancer, diverse protocols are used in order to detect early possible local recurrence. Our objective was to compare the results obtained by the endorectal ultrasonography (EUS) with other means of assessment. From 1988 to 1995, 140 patients have undergone curative surgery for rectal cancer. The pathological and sonographic lesions were evaluated according to the TNM classification. In 21 patients a local recurrence was diagnosed: 5 of those 21 were corresponding to T 3-4, N 0 and 16 to T 2-4, N 1 stage. All 21 showed evidence of local recurrence by EUS examination, 14 by digital rectal examination, 16 by colonoscopy, 18 by computed tomography, and the carcinoembryonic antigen level was high in 13 cases. In 12 patient who were asymptomatic EUS was positive in 12, digital rectal examination in 5, computer tomography in 9, colonoscopy in 8, and the CEA was increased in 4. Re-resection was possible in 15 cases, 6 with curative approach and 9 palliative. These findings suggest that EUS in care accurate in the early detection of local recurrence compared to other means of assessment review of the. The limited number of patients studies. Main form of assessment required further evaluation.

Adult↗
PubMed1997

Ecophysiological factors affecting growth, sporulation and survival of the biocontrol agent Penicillium oxalicum.

The effect of temperature, pH, water potential and sources of nitrogen and carbon on the biocontrol agent Penicillium oxalicum were studied in vitro. The fungus is xerotolerant, mesophillic and has a wide pH tolerance. The parameters evaluated (germination, germ tube length, growth rate and sporulation) showed different sensitivities to the environmental factors. Peptone and free amino acids gave the highest growth rates and high levels of sporulation. Xylose, mannose and fructose gave the highest growth rates and mannose induced strong sporulation. The effect of nutrients (mannose + arginine) and water potential was also studied in vivo. The xerotolerant character of the fungus was confirmed. From this study we consider Penicillium oxalicum ecologically competent to perform effectively as a biocontrol agent in the soil environment.

Journal Article↗
PubMed1997

Treatment of chronic hepatitis C with interferon-alpha. Clinical histological and virological implications.

OBJECTIVE: to identify pretreatment predictive factors of long-term biochemical and virological response to interferon-alpha in chronic hepatitis C and to determine the effects of a second course of interferon-alpha in patients who responded but relapsed after interferon withdrawal. DESIGN: retrospective analysis. SETTING: outpatient liver clinic of a tertiary hospital in Spain. PATIENTS: 112 patients with chronic hepatitis C were treated with recombinant interferon-alpha (3 MU three times a week for 6 months). Twenty-four patients who responded but relapsed after interferon withdrawal were treated with a second course of interferon (3 MU three times a week for 12 months). RESULTS: seventy-two patients were non-responders (64%), 11 patients had a sustained response (10%) and 29 patients responded but relapsed after interferon withdrawal (26%). Five (25%) of the 24 patients who relapsed and were treated with a second course of interferon experienced a sustained response (mean follow-up: 10 months). By multivariate analysis, four pretreatment variables were found to be predictive of a complete response: age < 40 years (p = 0.0004), history of IVDA (p = 0.001), low serum levels (p = 0.013), and genotype 3 (p = 0.01). Two variables were found to be predictive of a sustained response: short duration of HCV infection (p = 0.09) and genotype 3 (p = 0.01). Sustained responders appeared to have lower HCV-RNA levels than those with complete response who relapsed and non-responders. HCV viremia levels were not associated with the severity of liver histology, duration of disease or the source of hepatitis. CONCLUSIONS: in the present study a low sustained response rate was observed using a standard interferon-alpha regimen (3 MU three times a week for 6 months). The sustained response rate increased slightly with a second course of interferon-alpha (3 MU three times a week for 12 months) in patients with a complete response who relapsed after interferon withdrawal. Sustained response is related to viral genotype and duration of HCV infection.

Adolescent↗